Includes a revised taxonomic outline for the phyla Bacteroidetes, Planctomycetes, Chlamydiae, Spirochetes, Fibrobacteres, Fusobacteria, Acidobacteria, Verrucomicrobia, Dictyoglomi, and Gemmatimonadetes based upon the SILVA project as well as a description of more than 153 genera in 29 families. Includes many medically important taxa.

One of the most authoritative works in bacterial taxonomy, this resource has been extensively revised. This five volume second edition has been reorganized along phylogenetic lines to reflect the current state of prokaryotic taxonomy.